Question

Solve each equation. 9) log 4 (-a - 1) = log 4 (2a + 5)

Answer 1

 

$\displaystyle\bf\\9)\\\\log_4(-a-1)=log_4(2a+5)\\\\2a+5=-a-1\\\\2a+a=-1-5\\\\3a=-6\\\\a=\frac{-6}{3}\\\\\boxed{\bf~a=-2}\\\\Verify:\\\\log_4(-a-1)=log_4(-(-2)-1)=log_4(2-1)=log_4(1)=0\\\\log_4(2a+5)=log_4(2\times(-2)+5)=log_4(-4+5)=log_4(1)=0$